I have a dozen buff orpingtons and barred rocks (12 total chickens) and I have two roosts... 2x4's that run the length of one side of the coop... so 8 feet... one is lower than the other... I have hardware cloth underneath and use two dog crate pans under the roosts that pull out for easy cleaning...
no I was told not to round the edges and that they are much like pigeons and prefer a flat perch so I left it alone
I used some old railing posts I had sitting in the shed. They are maybe 2 or 3 inches round. I also have a 2 x 4, wide side up running along one wall that they use.
I have heard a 2x4 laid flat works well, especially in cold weather. My birds make do without a roost or nesting box. Small flock, currently 12 birds. Flat floor with straw. They lay eggs in one corner opposite the entrance, roost in the straw in the corner nearest the entrance. In cold weather they hunker down in the straw which keeps their feet warm. In hot weather like this some will sit on an old table outside others line up on the chicken ladder. They seem happy, my egg to bird ratio rarely goes below 80%, usually 90-100%.
I use Home Depot baluster rail. It's about 1.5" square, with slightly rounded corners. The hens seem very happy with it. I have two roots, set level so the hens don't compete for the highest roosting place. (Heh! There isn't one!)
I have always used tree limbs. My husband would cut off as straight as possible limbs, about a 2 1/2 to 3 inch diameter. So far it has worked well for us.
